similar to: R package for bootstrapping (comparing two quadratic regression models)

Hello, I am work with two quadratic regression models y=ax^2+bx+c with the function of lm. y1= observed migration distance of butterflies(y1=a1x^2+b1x+c1) y2= predicted migration distance of butterflies (based on body mass) (y2=a2x^2+b2x+c2) x= body mass of butterflies Now I would like to check the two regression model differ by testing if the coeffients (a, b, c) of the y1 and the y2

Hello I have a table describing butterfly range traits. It is composed of three columns as below Species name range size (X) latitude of range midpoint (Y) There are 11 kinds of butterflies. Each has its range size, and the latitude of each range midpoint ranges from 9 to 19. I would like to have the average range size of every degree of latitude. For example, the average range

Hello, I am work with a linear regression model: y=ax+b with the function of lm. y= observed migration distance of butterflies x= predicted migration distance of butterflies Usually the result will show if the linear term a is significantly different from zero based on the p-value. Now I would like to test if the linear term is significantly different from one. (because I want to know

Hello I have a table describing butterfly range traits. It is composed of three columns as below Species name range size (X) latitude of range midpoint (Y) There are 11 kinds of butterflies. Each has its range size, and the latitude of each range midpoint ranges from 9 to 19. I would like to have the average range size of every degree of latitude. For example, the average range

Greetings, I am interested in creating a stepwise fixed order regression function. There's a function for this already called add1( ). The F statistics are calculated using type 2 anova (the SS and the F changes don't match SPSS's). You can see my use of this at the very end of the email. What I want: a function to make an anova table with f changes and delt R^2. I ran into

Hello, i'm fairly familiar with R and use it every now and then for math related tasks. I have a simple non polynomial function that i would like to approximate with a polynomial. I already looked into poly, but was unable to understand what to do with it. So my problem is this. I can generate virtually any number of datapoints and would like to find the coeffs a1, a2, ... up to a given

Hello One of my packages, untb_1.3-2, passes R CMD check under MacOSX (and apparently the systems used in the package check summary page on CRAN) but fails with the following message on R-2.6.0.tgz compiled last night on my (home) linux box. I hasten to add that I have never seen this error before on home-compiled pre-releases of R-2.6.0. Can anyone help me understand what is going on?

Hello, I want to know if two quadratic regressions are significantly different. I was advised to make the test using step 1 bootstrapping both quadratic regressions and get their slope coefficients. (Let's call the slope coefficient *â*^1 and *â*^2) step 2 use the slope difference *â*^1-*â*^2 and bootstrap the slope coefficent step 3 find out the sampling distribution above and

Hello, I have two very rudimentary questions regarding the random effects terms in the lme and lmer functions. I apologize if this also partly strays into a general statistics question, but I'm a bit new to this all. So hopefully it'll be a quick problem to sort out... Here is my experimental setup: I raised butterflies in 5 different testing chambers all set to different

I took function mdct_butterfly_8 and write out transformation matrix. Then I rewrote this matrix into sequence of additions and substractions (see attachement). As I suspected I got the same as in the original code but I swaped some rows to get little higher speed. I hope I'll do the same with 16 point butterfly function combined with 8 point butterflies in a month. Who still believe that this

Hi there, I am trying to reorganized my data sets so that it is easy for MARK to read it. Basically I have the encounter histories of 1837 butterflies The data looks like this the first 4 columns are the occasions and the last two code for male and female > t1 t2 t3 t4 M F > 1 0 0 0 1 0 male capture on time1 but not seen on time 2, 3 > and 4 > 1 0 0 0

Dear all, I am trying to use the GEE methodology to fit a trend for the number of butterflies observed at several sites. In total, there are 66 sites, and 19 years for which observations might be available. However, only 326 observations are available (instead of 1254). For the time being, I ignore the large number of missing values, and the fact that GEE is only valid under MCAR. When I run the

Hi, Included is an R.script that came from a much large date set being read in to R from a .txt file. Why is it that the first line codes with an error, but the second line works fine? Is there some line length limit in R? This happens at random places all through my data. Any help would be appreciated. -------------------------------------------------------------------- Bill Wyatt

In mdct.c there's some functions including some-point butterfly. In 32-point and 16-point there are calling of smaller-point function everytime twice on each half of data. When I looked on it I found that's just linear algebra. So it can be rewritten to matrix multiplication. Some one can say: there's optimization on in register working. But imagine there's one calling 32-point,

Dear List, I want to compare the presence and absence of bird species based on the sites in a matrix. The matrix has 5 rows for Island A, B, C, D, and E. It has 100 columns for bird species D001-D100. In each cell of the matrix, the presence-absence of bird species will be recorded as 1 or 0. (For example, if species D001 is found on Island D, the matrix cell of species D001 and Island D

Hello, This is Elaine. I am using R 3.0 to download package vegan but failed. The warning message is package ‘vegan’ successfully unpacked and MD5 sums checked Warning: unable to move temporary installation ‘C:\Users\elaine\Documents\R\win-library\3.0\file16c82da53b1b\vegan’ to ‘C:\Users\elaine\Documents\R\win-library\3.0\vegan’ I cannot find the folder \file16c82da53b1b\ below

Hi. Thank you very much in advance for your help. I have generated data from two simple linear models and used k-means clustering (stats4) to identify two clusters in the generated data. Next, I would like to do simple linear regression for each separate cluster. I can do this if I first use the cluster labels to define two separate data frames with the subset function. However, I would

Dear list I have a matrix composed of islandID as rows and speciesID as columns. IslandID: Island A, B, C….O (15 islands in total) SpeciesID: D0001, D0002, D0003….D0100 (100 species in total) The cell of the matrix describes presence (1) or absence (0) of the species in an island. Now I would like to search the species with absence (0) in all the islands (Island A to Island O.)

Hello, I am making a boxplot of 13 boxes. I tried to color the box using 13 colors but failed. Only red and brown were displayed. Green, blue, and grey disappeared. Please kindly advise modification after checking the code below. Thank you in advance. Elaine R code # data input dataN <-read.csv("H:/a_mig_distance_B_NB/R_data/Mig_bird_586_20120925.csv",header=T, row.names=1)

Hello This is Elaine. I am using package lattice to generate boxplots. Using Richard's code, the display was almost perfect except the outlier shape. Based on the following code, the outliers are vertical lines. However, I want the outliers to be empty circles. Please kindly help how to modify the code to change the outlier shapes. Thank you. code package (lattice) dataN <-